When httmax > 2100 , the graphite crystallites grow rapidly , and the charging - discharging capacities of the samples increase , too . the mechanism of storing lithium - ions convert s to the intercalation of the lithium ions into the layers of graphite crystallites . the charging - discharging curves of the samples look like the letter " u " and have low potential flat plateaus Htt _ ( max ) 2100时，石墨微晶迅速成长，充、放电容量迅速增大，充、放电曲线为“ u ”字形，充、放电平台低而平稳，表现出典型的“石墨微晶层间嵌锂”机制。
The contact freeform surface meaurement system the authors are developing is introduced in this paper , it is the application of cmm in the reverse engineering of part . the components of its software and hardware are analyed . under the circumstances of cad modelis unknown , somecirtical problems are studied such as the measurement points adaptive localization , the measurement path , layout and measurement data disoposal etc . based on measuring the curved surface of the cam , the scaning software have be designed in measuring the curved surface in cmm . the cmm ' s data can transfer to cad / cam system 分析了其软硬件的组成，并对在cad模型未知的情况下，测量系统软件中的一些关键技术，如测点的自适应分布、测量路径的规划和测量数据的处理方法等作了研究。并以凸轮轮廓曲线为例，编制了相应的曲线面轮廓扫描软件，并使三坐标测量机的测量数据转换为cad cam能接受的图形信息格式。
